- Xylem and phloem

• Plants have two separate types of transparent vessels- xylem and phloem- for transporting stuff around. both types of vessels go to every part of the plant in a continuous system but they’re totally separate.
• Made of columns of living cells called sieve tube elements.

  These have perforated end-plates to allow stuff to flow through.
• Sieve tube elements have no nucleus. This means that they cant survive on their own, so each sieve tube element has a companion cell. These cells carry out the living functions for both themselves and their sieve cells.
• Phloem vessels transport food substances (mainly sugars) both up and down the stem to growing and storage tissues. This movement of food substances around the plant is known as translocation.
• Phloem Tubes Transport Food
• Xylem tubes Take water UP
• Made of dead cells joined end to end with no end walls between them and a hole (lumen) down the middle.
• 1. The thick side walls are made of cellulose. They're strong and stiff, which gives the plant support. The cell walls are also strengthened with a material called lignin.
• 1. They carry water and minerals from the roots up the shoot to the leaves in the transpiration stream (see below).